Removed all sets and maps, set linkedhashmaps and linkedhashsets explicitly

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/ModularMovementModel.java

@@ -115,11 +115,11 @@ public class ModularMovementModel implements MovementModel, EventHandler, Attrac
 	
 	protected AttractionPointViz attractionPointViz;
 
-	protected Set<SimLocationActuator> moveableHosts = new LinkedHashSet<SimLocationActuator>();
+	protected LinkedHashSet<SimLocationActuator> moveableHosts = new LinkedHashSet<SimLocationActuator>();
 
-	protected Map<SimLocationActuator, PositionVector> currentTargets = new LinkedHashMap<>();
+	protected LinkedHashMap<SimLocationActuator, PositionVector> currentTargets = new LinkedHashMap<>();
 
-	protected Map<SimLocationActuator, RouteSensorComponent> routeSensorComponents = new LinkedHashMap<>();
+	protected LinkedHashMap<SimLocationActuator, RouteSensorComponent> routeSensorComponents = new LinkedHashMap<>();
 
 	protected boolean initialized = false;
 
@@ -366,7 +366,7 @@ public class ModularMovementModel implements MovementModel, EventHandler, Attrac
 	 * === GETTER AND SETTER FUNCTIONS
 	 * =====================================================================================================
 	 */
-	public Set<SimLocationActuator> getAllLocationActuators() {
+	public LinkedHashSet<SimLocationActuator> getAllLocationActuators() {
 		return moveableHosts;
 	}
 

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/SocialGroupMovementModel.java

@@ -20,9 +20,8 @@
 
 package de.tud.kom.p2psim.impl.topology.movement.modularosm;
 
+import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
-import java.util.Map;
-import java.util.Set;
 
 import de.tud.kom.p2psim.api.scenario.ConfigurationException;
 import de.tud.kom.p2psim.api.topology.Topology;
@@ -55,7 +54,7 @@ public class SocialGroupMovementModel extends ModularMovementModel {
 	protected IGroupFormingBehavior groupFormingBehavior;
 	protected IGroupEncounterBehavior groupEncounterBehavior;
 		
-	private Set<SimLocationActuator> singleHosts = new LinkedHashSet<SimLocationActuator>();
+	private LinkedHashSet<SimLocationActuator> singleHosts = new LinkedHashSet<SimLocationActuator>();
 	private int numberOfSingleHosts;
 		
 	
@@ -380,11 +379,11 @@ public class SocialGroupMovementModel extends ModularMovementModel {
 		this.numberOfSingleHosts = numberOfSingleHosts;
 	}
 	
-	public Set<SimLocationActuator> getSingleHosts(){
+	public LinkedHashSet<SimLocationActuator> getSingleHosts(){
 		return singleHosts;
 	}	
 
-	public Map<SimLocationActuator, PositionVector> getCurrentTargets(){
+	public LinkedHashMap<SimLocationActuator, PositionVector> getCurrentTargets(){
 		return currentTargets;
 	}
 }

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/AbstractAttractionProvider.java

@@ -40,7 +40,7 @@ public class AbstractAttractionProvider implements IAttractionProvider {
 		this.worldDimension = Binder.getComponentOrNull(Topology.class).getWorldDimensions();		
 	}
 	
-	public List<AttractionPoint> getAttractionPoints() {
+	public LinkedList<AttractionPoint> getAttractionPoints() {
 		return new LinkedList<AttractionPoint>(attractionPoints);
 	}
 	

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/AttractionPoint.java

@@ -21,7 +21,6 @@
 package de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction;
 
 import java.util.LinkedHashMap;
-import java.util.Map;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.IAttractionBasedMovementAnalyzer;
 import de.tud.kom.p2psim.impl.topology.util.PositionVector;
 import de.tudarmstadt.maki.simonstrator.api.Monitor;
@@ -39,7 +38,7 @@ import de.tudarmstadt.maki.simonstrator.api.util.XMLConfigurableConstructor;
  * @version 1.2, 24.01.2020 - added pause time interval, weight, and radius exclusively to this class, because {@link BasicAttractionPoint} should be just a named point.
  */
 public class AttractionPoint extends BasicAttractionPoint {	
-	protected static Map<String, AttractionPoint> instances = new LinkedHashMap<>();
+	protected static LinkedHashMap<String, AttractionPoint> instances = new LinkedHashMap<>();
 	
 	protected long pauseTimeMin = -1;
     protected long pauseTimeMax = -1;
@@ -141,6 +140,10 @@ public class AttractionPoint extends BasicAttractionPoint {
     @Override
     public void setRadius(double radius) {
         this.radius = radius;
+        
+        if(radius > 0) {
+			this.area = Math.PI * Math.pow(radius, 2);
+		}	
     }	    
 
 	@Override

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/CsvAttractionGenerator.java

@@ -64,7 +64,7 @@ public class CsvAttractionGenerator extends AbstractAttractionProvider {
 	}
 	
 	@Override
-	public List<AttractionPoint> getAttractionPoints() {
+	public LinkedList<AttractionPoint> getAttractionPoints() {
 		if (super.getAttractionPoints().isEmpty()) {			
 			readData();
 		}

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/EquidistantSquareAttractionGenerator.java

@@ -20,6 +20,7 @@
 
 package de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction;
 
+import java.util.LinkedList;
 import java.util.List;
 import de.tud.kom.p2psim.impl.topology.util.PositionVector;
 import de.tudarmstadt.maki.simonstrator.api.util.XMLConfigurableConstructor;
@@ -42,7 +43,7 @@ public class EquidistantSquareAttractionGenerator extends AbstractAttractionProv
 	}
 
 	@Override
-	public List<AttractionPoint> getAttractionPoints() {
+	public LinkedList<AttractionPoint> getAttractionPoints() {
 		if(super.getAttractionPoints().isEmpty())
 			createAttractionPoints();
 		

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/JSONAttractionGenerator.java

@@ -23,6 +23,7 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction;
 import java.io.FileInputStream;
 import java.io.FileNotFoundException;
 import java.io.IOException;
+import java.util.LinkedList;
 import java.util.List;
 import org.apache.commons.io.IOUtils;
 import org.json.JSONArray;
@@ -70,7 +71,7 @@ public class JSONAttractionGenerator extends AbstractAttractionProvider {
 	}
 	
 	@Override
-	public List<AttractionPoint> getAttractionPoints() {
+	public LinkedList<AttractionPoint> getAttractionPoints() {
 		if(super.getAttractionPoints().size() == 0) {
 			createAttractionPoints();
 		}

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/RandomAttractionGenerator.java

@@ -75,7 +75,7 @@ public class RandomAttractionGenerator extends AbstractAttractionProvider {
 	}
 
 	@Override
-	public List<AttractionPoint> getAttractionPoints() {
+	public LinkedList<AttractionPoint> getAttractionPoints() {
 		if (!numberOfAPsSet) {
 			throw new ConfigurationException(
 					"Number of Attraction Points is not set in RandomAttractionGenerator!");
@@ -88,7 +88,7 @@ public class RandomAttractionGenerator extends AbstractAttractionProvider {
 	}
 	
 	private void createAttractionPoints() {
-		List<AttractionPoint> result = new LinkedList<AttractionPoint>();
+		LinkedList<AttractionPoint> result = new LinkedList<AttractionPoint>();
 		
 		// make a break counter to prevent more than 10 iterations and an infinity loop in general.
 		int c = 0;

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/attraction/hostcount/HostAtAttractionPointCounter.java

@@ -65,7 +65,7 @@ public class HostAtAttractionPointCounter {
 	 * @param IAttractionPoint The {@link IAttractionPoint} to be checked.
 	 * @return Integer
 	 */
-	public static int getHostCountOfAttractionPoint(IAttractionPoint attractionPoint, Set<SimLocationActuator> hostsToConsider) {
+	public static int getHostCountOfAttractionPoint(IAttractionPoint attractionPoint, LinkedHashSet<SimLocationActuator> hostsToConsider) {
 		return getHostsOfAttractionPoint(attractionPoint, hostsToConsider).size();
 	}
 	
@@ -75,9 +75,9 @@ public class HostAtAttractionPointCounter {
 	 * @param IAttractionPoint The {@link IAttractionPoint} to be checked.
 	 * @return Set<SimLocationActuator>
 	 */
-	public static Set<SimLocationActuator> getHostsOfAttractionPoint(IAttractionPoint attractionPoint, Set<SimLocationActuator> hostsToConsider) {
+	public static LinkedHashSet<SimLocationActuator> getHostsOfAttractionPoint(IAttractionPoint attractionPoint, Set<SimLocationActuator> hostsToConsider) {
 		
-		Set<SimLocationActuator> hosts = new LinkedHashSet<SimLocationActuator>();
+		LinkedHashSet<SimLocationActuator> hosts = new LinkedHashSet<SimLocationActuator>();
 		
 		for(SimLocationActuator h : hostsToConsider) {		
 			if(isHostInAttractionPointArea(h, attractionPoint)) {

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/MovementGroupContainer.java

@@ -22,13 +22,8 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups;
 
 import java.util.LinkedHashMap;
 import java.util.LinkedHashSet;
-import java.util.Map;
-import java.util.Set;
-
 import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
-import de.tud.kom.p2psim.impl.topology.movement.modularosm.ISocialGroupMovementAnalyzer;
 import de.tud.kom.p2psim.impl.util.Tuple;
-import de.tudarmstadt.maki.simonstrator.api.Monitor;
 import de.tudarmstadt.maki.simonstrator.api.Time;
 
 /**
@@ -40,15 +35,15 @@ import de.tudarmstadt.maki.simonstrator.api.Time;
 public class MovementGroupContainer {
 	private static MovementGroupContainer instance;
 
-	private Set<SocialMovementGroup> groups;
+	private LinkedHashSet<SocialMovementGroup> groups;
 
 	// Mappings
-	private Map<SimLocationActuator, Long> leftGroupAtTime;
-	private Map<SimLocationActuator, Boolean> hasMerged;
-	private Map<SimLocationActuator, Long> mergedAtTime;
+	private LinkedHashMap<SimLocationActuator, Long> leftGroupAtTime;
+	private LinkedHashMap<SimLocationActuator, Boolean> hasMerged;
+	private LinkedHashMap<SimLocationActuator, Long> mergedAtTime;
 	
 	// Waiting Groups, used for encounter strategy Wait. Includes remaining waiting time and last update time
-	public Map<SocialMovementGroup, Tuple<Long, Long>> waitingGroups;
+	public LinkedHashMap<SocialMovementGroup, Tuple<Long, Long>> waitingGroups;
 
 	private MovementGroupContainer() {
 		groups = new LinkedHashSet<>();
@@ -282,15 +277,15 @@ public class MovementGroupContainer {
 	 * 
 	 * @author Marcel Verst
 	 */
-	public Set<SimLocationActuator> getGroupMembers(SimLocationActuator host){
+	public LinkedHashSet<SimLocationActuator> getGroupMembers(SimLocationActuator host){
 		return getGroupOfHost(host).getMembers();
 	}
 
-	public Set<SocialMovementGroup> getGroups() {
+	public LinkedHashSet<SocialMovementGroup> getGroups() {
 		return groups;
 	}
 
-	public void setGroups(Set<SocialMovementGroup> groups) {
+	public void setGroups(LinkedHashSet<SocialMovementGroup> groups) {
 		this.groups = groups;
 	}
 
@@ -307,23 +302,23 @@ public class MovementGroupContainer {
 		}
 	}
 
-	public void setLeftGroupAtTime(Map<SimLocationActuator, Long> leftGroupAtTime) {
+	public void setLeftGroupAtTime(LinkedHashMap<SimLocationActuator, Long> leftGroupAtTime) {
 		this.leftGroupAtTime = leftGroupAtTime;
 	}
 
-	public Map<SimLocationActuator, Boolean> getHasMerged() {
+	public LinkedHashMap<SimLocationActuator, Boolean> getHasMerged() {
 		return hasMerged;
 	}
 
-	public void setHasMerged(Map<SimLocationActuator, Boolean> hasMerged) {
+	public void setHasMerged(LinkedHashMap<SimLocationActuator, Boolean> hasMerged) {
 		this.hasMerged = hasMerged;
 	}
 
-	public Map<SimLocationActuator, Long> getMergedAtTime() {
+	public LinkedHashMap<SimLocationActuator, Long> getMergedAtTime() {
 		return mergedAtTime;
 	}
 
-	public void setMergedAtTime(Map<SimLocationActuator, Long> mergedAtTime) {
+	public void setMergedAtTime(LinkedHashMap<SimLocationActuator, Long> mergedAtTime) {
 		this.mergedAtTime = mergedAtTime;
 	}
 }
\ No newline at end of file

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/SocialMovementGroup.java

@@ -22,7 +22,6 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups;
 
 import java.util.LinkedHashSet;
 import java.util.Random;
-import java.util.Set;
 import java.util.UUID;
 
 import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
@@ -39,6 +38,7 @@ public class SocialMovementGroup {
 	
 	public final UUID groupID;
 	
+	private Random rand = Randoms.getRandom(SocialMovementGroup.class);
 	private SimLocationActuator leader;
 	private LinkedHashSet<SimLocationActuator> members;
 
@@ -67,7 +67,7 @@ public class SocialMovementGroup {
 	 * @param Set<SimLocationActuator> All participants of the group.
 	 * @param int The ID of the group.
 	 */
-	public SocialMovementGroup(Set<SimLocationActuator> participants) {
+	public SocialMovementGroup(LinkedHashSet<SimLocationActuator> participants) {
 		
 		this.groupID = UUID.randomUUID();
 		
@@ -115,8 +115,7 @@ public class SocialMovementGroup {
 	 */
 	public SimLocationActuator getRandomMember() {
 		
-		if(members.size() > 1) {
-			Random rand = Randoms.getRandom(SocialMovementGroup.class);
+		if(members.size() > 1) {			
 			int item = rand.nextInt(members.size() - 1);
 			int i = 0;
 			
@@ -170,11 +169,11 @@ public class SocialMovementGroup {
 		return members.size();
 	}
 	
-	public Set<SimLocationActuator> getMembers() {
+	public LinkedHashSet<SimLocationActuator> getMembers() {
 		return members;
 	}
 	
-	public void setMembers(Set<SimLocationActuator> participants) {
+	public void setMembers(LinkedHashSet<SimLocationActuator> participants) {
 		this.members = new LinkedHashSet<>(participants);
 	}
 	

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/groupencounter/AbstractGroupEncounter.java

@@ -22,8 +22,6 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupencounte
 
 import java.util.LinkedHashSet;
 import java.util.Random;
-import java.util.Set;
-
 import de.tud.kom.p2psim.api.scenario.ConfigurationException;
 import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.ISocialGroupMovementAnalyzer;
@@ -100,14 +98,14 @@ public abstract class AbstractGroupEncounter implements IGroupEncounterBehavior
 	 *
 	 * @return 
 	 */
-	private Set<Pair<SocialMovementGroup>> getEncounteringGroups() {
+	private LinkedHashSet<Pair<SocialMovementGroup>> getEncounteringGroups() {
 		if(!enableGroupEncounters)
 			return null;
 		
-		Set<Pair<SocialMovementGroup>> encounteringGroups = new LinkedHashSet<>();
-		Set<SocialMovementGroup> alreadyProcessed = new LinkedHashSet<>();
+		LinkedHashSet<Pair<SocialMovementGroup>> encounteringGroups = new LinkedHashSet<>();
+		LinkedHashSet<SocialMovementGroup> alreadyProcessed = new LinkedHashSet<>();
 				
-		Set<SocialMovementGroup> allGroups = groupCon.getGroups();
+		LinkedHashSet<SocialMovementGroup> allGroups = groupCon.getGroups();
 		
 		for(SocialMovementGroup group1 : allGroups) {
 			for(SocialMovementGroup group2 : allGroups) {
@@ -148,7 +146,7 @@ public abstract class AbstractGroupEncounter implements IGroupEncounterBehavior
 		if(!enableGroupEncounters)
 			return;			
 		
-		Set<Pair<SocialMovementGroup>> encounteringGroups = getEncounteringGroups();
+		LinkedHashSet<Pair<SocialMovementGroup>> encounteringGroups = getEncounteringGroups();
 		
 		if(encounteringGroups == null || encounteringGroups.isEmpty()) {
 			return;
@@ -269,7 +267,7 @@ public abstract class AbstractGroupEncounter implements IGroupEncounterBehavior
 		SocialMovementGroup large = getLargerGroup(group1, group2);
 		SocialMovementGroup small = getSmallerGroup(group1, group2);
 
-		Set<SimLocationActuator> toRemove = new LinkedHashSet<>(small.getMembers());
+		LinkedHashSet<SimLocationActuator> toRemove = new LinkedHashSet<>(small.getMembers());
 		
 		for(SimLocationActuator participant : toRemove) {
 			small.removeHostFromGroup(participant);

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/groupencounter/IGroupEncounterBehavior.java

@@ -20,11 +20,9 @@
 
 package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupencounter;
 
-import java.util.Set;
 
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.SocialGroupMovementModel;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.SocialMovementGroup;
-import de.tudarmstadt.maki.simonstrator.api.common.datastructures.Pair;
 
 /**
  * Handles group encounters. Check group encounters based on the leaders location of {@link SocialMovementGroup}s.

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/groupforming/AbstractGroupForming.java

@@ -21,6 +21,7 @@
 package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupforming;
 
 import java.util.LinkedHashMap;
+import java.util.LinkedHashSet;
 import java.util.Map;
 import java.util.Random;
 import java.util.Set;
@@ -199,7 +200,7 @@ public abstract class AbstractGroupForming implements IGroupFormingBehavior {
 	 * 
 	 * @param Set<SimLocationActuator> The members which want to form a group.
 	 */
-	protected void createGroup(Set<SimLocationActuator> members) {		
+	protected void createGroup(LinkedHashSet<SimLocationActuator> members) {		
 		SocialMovementGroup group = new SocialMovementGroup(members);
 	
 		// force a new attraction point assignment on the leader

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/groups/groupforming/DefaultGroupForming.java

@@ -23,12 +23,9 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.groupforming;
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.LinkedList;
-import java.util.Set;
-
 import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
 import de.tud.kom.p2psim.api.topology.movement.local.LocalMovementStrategy;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.ISocialGroupMovementAnalyzer;
-import de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction.IAttractionProvider;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.attraction.hostcount.HostAtAttractionPointCounter;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.groups.SocialMovementGroup;
 import de.tud.kom.p2psim.impl.topology.movement.modularosm.transition.IAttractionAssigmentStrategy;
@@ -97,12 +94,12 @@ public class DefaultGroupForming extends AbstractGroupForming {
 			return;
 		}
 
-		Set<SimLocationActuator> hostsAtAttractionPoint = HostAtAttractionPointCounter.getHostsOfAttractionPoint(apCandidate, movementModel.getAllLocationActuators());
+		LinkedHashSet<SimLocationActuator> hostsAtAttractionPoint = HostAtAttractionPointCounter.getHostsOfAttractionPoint(apCandidate, movementModel.getAllLocationActuators());
 		
 		int numberOfHostsInAttractionPoint = hostsAtAttractionPoint.size();
 		int groupSize = this.rndGroupSize(numberOfHostsInAttractionPoint);
 					
-		Set<SimLocationActuator> groupCandidates = new LinkedHashSet<>();
+		LinkedHashSet<SimLocationActuator> groupCandidates = new LinkedHashSet<>();
 		
 		// shuffle the hosts at the attraction point (more randomness ftw!) 
 		LinkedList<SimLocationActuator> randomShuffledHostsAtAttractionPoint = new LinkedList<>(hostsAtAttractionPoint);
@@ -169,9 +166,9 @@ public class DefaultGroupForming extends AbstractGroupForming {
 		LocalMovementStrategy movementStrategy = movementModel.getMovementStrategy();
 		IAttractionAssigmentStrategy transition = movementModel.getAttractionAssignmentStrategy();
 
-		Set<SocialMovementGroup> groupsToRemove = new LinkedHashSet<>();
+		LinkedHashSet<SocialMovementGroup> groupsToRemove = new LinkedHashSet<>();
 
-		Set<SocialMovementGroup> groups = groupCon.getGroups();
+		LinkedHashSet<SocialMovementGroup> groups = groupCon.getGroups();
 		
 		for(SocialMovementGroup group : groups) {
 			SimLocationActuator leader = group.getLeader();

src/de/tud/kom/p2psim/impl/topology/movement/modularosm/transition/AbstractAttractionBasedAssignmentStrategy.java

@@ -22,8 +22,6 @@ package de.tud.kom.p2psim.impl.topology.movement.modularosm.transition;
 
 import java.util.LinkedHashMap;
 import java.util.LinkedList;
-import java.util.List;
-import java.util.Map;
 import java.util.Random;
 
 import de.tud.kom.p2psim.api.topology.movement.SimLocationActuator;
@@ -45,10 +43,10 @@ public abstract class AbstractAttractionBasedAssignmentStrategy implements IAttr
 	
 	protected IAttractionProvider attractionProvider;
 		
-	protected Map<SimLocationActuator, IAttractionPoint> assignments = new LinkedHashMap<>();	
-	protected Map<SimLocationActuator, IAttractionPoint> lastAssignments = new LinkedHashMap<>();
+	protected LinkedHashMap<SimLocationActuator, IAttractionPoint> assignments = new LinkedHashMap<>();	
+	protected LinkedHashMap<SimLocationActuator, IAttractionPoint> lastAssignments = new LinkedHashMap<>();
 	
-	private List<AttractionAssignmentListener> listeners = new LinkedList<>();
+	private LinkedList<AttractionAssignmentListener> listeners = new LinkedList<>();
 	
 	protected long defaultPauseTimeMin = 0;	
 	protected long defaultPauseTimeMax = 0;
@@ -141,7 +139,7 @@ public abstract class AbstractAttractionBasedAssignmentStrategy implements IAttr
 	protected IAttractionPoint getNewAttractionPointAssignment(SimLocationActuator host) {		
 			
 		double score = rnd.nextDouble();		
-		List<IAttractionPoint> candidates = new LinkedList<>();
+		LinkedList<IAttractionPoint> candidates = new LinkedList<>();
 		for (IAttractionPoint ap : attractionProvider.getAttractionPoints()) {
 			// skip null values (should never occur!)
 			if(ap == null) {